Japan Doesn't Attack the US in 1941.

Sciox · Dec 22, 2013

From what I've read the main motivator behind the Pearl Harbour attack was that Japan believed that if it moved against the allies in South East Asia, in particular the Dutch East Indies, America would declare war.

Lets say Yamamoto manages to convince enough people that America isn't worth fighting, at least while fighting the British Empire and the Netherlands, so instead of attack Pearl Harbour Japan bypasses the Philippines and goes straight for the Royal Navy at Hong Kong and Singapore before moving onto the Dutch East Indies. Japan delivers a declaration of war to London a day before the fleet attacks the first targets.

Although it's a blatant act of aggression could the people in the US who wanted war with Japan drum up the political support in Congress for a declaration of war and if they did, could the US fight Japan as effectively as OTL without the massive call to arms moment that Pearl Harbour was.

deathscompanion1 · Dec 22, 2013

Sciox said:
From what I've read the main motivator behind the Pearl Harbour attack was that Japan believed that if it moved against the allies in South East Asia, in particular the Dutch East Indies, America would declare war.

Lets say Yamamoto manages to convince enough people that America isn't worth fighting, at least while fighting the British Empire and the Netherlands, so instead of attack Pearl Harbour Japan bypasses the Philippines and goes straight for the Royal Navy at Hong Kong and Singapore before moving onto the Dutch East Indies. Japan delivers a declaration of war to London a day before the fleet attacks the first targets.

Although it's a blatant act of aggression could the people in the US who wanted war with Japan drum up the political support in Congress for a declaration of war and if they did, could the US fight Japan as effectively as OTL without the massive call to arms moment that Pearl Harbour was.

That's an even bigger gamble than OTL from their point of view. You now have an undamaged American fleet sitting right on top of your supply lines. The USA had been hostile for years and isolationism was already fading, if the Japanese go on a rampage then FDR will take action.

Hoist40 · Dec 22, 2013

deathscompanion1 said:
That's an even bigger gamble than OTL from their point of view. You now have an undamaged American fleet sitting right on top of your supply lines. The USA had been hostile for years and isolationism was already fading, if the Japanese go on a rampage then FDR will take action.

But its a undamaged fleet without enough tankers, ammo ships, supply ships, repair ships, amphibious ships, troops, etc to do much more the raid the outer islands held by the Japanese.

FDR then has to get a declaration of war from Congress over the Japanese conquest of European colonies, when that same Congress would not declare war when European countries were being beaten.

The only real risk is if the Philippines which sits on the Japanese southern trade routes gets built up by the US enough to be a real threat to the Japanese. However Europe was still the focus of US efforts and with few supply ships in the Pacific the build up was going very slow. Especially if the Japanese grab Dutch and British islands in the south which would mean that the Philippines were totally surrounded by Japanese held islands making resupply very difficult.

Sure its a risk but a lot better then sinking some US battleships which were no real threat and destroying some aircraft which could be replaced with a couple of weeks US production while at the same time getting the US 110% into a war with Japan.

The Japanese did grab French Indo-China without attacking the US, maybe they could be convinced to go after the Dutch first and if the British intervened go after them leaving the US stuck without a declaration of war

CalBear · Dec 22, 2013

This is a oft discussed subject here. A search of topics will get you a wealth of discussions; however, to briefly address the issue...

The Japanese had no choice strategically but to calculate that the U.S. would react with hostility to the attack against the Southern Resource Area. The U.S. had, almost accidentally, secured positions in the Pacific that were quite literally perfectly placed to mortally threaten Japan's military goals, namely to secure the necessary resources and establish a defensive perimeter that would allow the Empire to successfully defend its new acquisitions.

Specifically, the Philippines, especially the U.S. positions on Luzon, were ideally placed to interdict any movement of materials from the Malay Peninsula, DEI and Indochina, while also providing an ideal position to engage Japanese bases in Formosa that were critical to the conduct of the war in China. The U.S. base on Guam, while still undeveloped, was slated for improvements that would make Japan's position on Saipan (which was supposed to be temporary under League Mandate) completely untenable while Wake was nearly ideally placed to provide basing of long range air power to interdict the rest of the Mandates. Once you add in Johnson Island, Palmyra Atoll, and American Samoa, the U.S. had positions across the Pacific that would have rendered any Japanese effort to establish a defensive perimeter impossible.

In planning for war you must account for what your enemy could do. You have to assume that your opponent will be competent (it is better to pretend that your enemy is at least as capable as you are, and to account for all the OPFOR potential, although this is exceptionally difficult to do in practice, and something that the Japanese did not do in the planning for the December 1941 Offensive). The U.S. was clearly not a friend, it had long been hostile to Japan's expansion goals in China and had acted with considerable hostility on the economic front (whether this was justified or not isn't really germane to the planning process) to every Japanese move since 1937. To believe that the U.S. would not react to a massive provocation like the attack on the Southern Resource Area would have been an act of lunacy by the Imperial planners. The Japanese planning staff was over confident and ignorant about American politics, but they were not lunatics. The U.S. potential had to be addressed.

Curiousone · Dec 22, 2013

CalBear said:
This is a oft discussed subject here. A search of topics will get you a wealth of discussions; however, to briefly address the issue...

The Japanese had no choice strategically but to calculate that the U.S. would react with hostility to the attack against the Southern Resource Area. The U.S. had, almost accidentally, secured positions in the Pacific that were quite literally perfectly placed to mortally threaten Japan's military goals, namely to secure the necessary resources and establish a defensive perimeter that would allow the Empire to successfully defend its new acquisitions.

Specifically, the Philippines, especially the U.S. positions on Luzon, were ideally placed to interdict any movement of materials from the Malay Peninsula, DEI and Indochina, while also providing an ideal position to engage Japanese bases in Formosa that were critical to the conduct of the war in China. The U.S. base on Guam, while still undeveloped, was slated for improvements that would make Japan's position on Saipan (which was supposed to be temporary under League Mandate) completely untenable while Wake was nearly ideally placed to provide basing of long range air power to interdict the rest of the Mandates. Once you add in Johnson Island, Palmyra Atoll, and American Samoa, the U.S. had positions across the Pacific that would have rendered any Japanese effort to establish a defensive perimeter impossible.

In planning for war you must account for what your enemy could do. You have to assume that your opponent will be competent (it is better to pretend that your enemy is at least as capable as you are, and to account for all the OPFOR potential, although this is exceptionally difficult to do in practice, and something that the Japanese did not do in the planning for the December 1941 Offensive). The U.S. was clearly not a friend, it had long been hostile to Japan's expansion goals in China and had acted with considerable hostility on the economic front (whether this was justified or not isn't really germane to the planning process) to every Japanese move since 1937. To believe that the U.S. would not react to a massive provocation like the attack on the Southern Resource Area would have been an act of lunacy by the Imperial planners. The Japanese planning staff was over confident and ignorant about American politics, but they were not lunatics. The U.S. potential had to be addressed.

Not to threadjack, but what would you do as a Japanese Militarist in sway of the Empire in 1941?

Go North (Russia)?
Ignore the American Oil blockade for now, let yourself lose ground in China for a while while waiting to see what happens in Europe (Delay, pick the winner)?
Go South without attacking America (UK+Dutch+Cross fingers)?
Go South with attacking America but do it differently (UK+Dutch+U.S+'but')?
Declare Peace with China, War with Germany/Italy (Machiavellian Marvelous Bastard)?

If none of the above,

What sort of terms do you try and negotiate for with China, America?

CalBear · Dec 22, 2013

Curiousone said:
Not to threadjack, but what would you do as a Japanese Militarist in sway of the Empire in 1941?

Go North (Russia)?
Ignore the American Oil blockade for now, let yourself lose ground in China for a while while waiting to see what happens in Europe (Delay, pick the winner)?
Go South without attacking America (UK+Dutch+Cross fingers)?
Go South with attacking America but do it differently (UK+Dutch+U.S+'but')?
Declare Peace with China, War with Germany/Italy (Machiavellian Marvelous Bastard)?

If none of the above,

What sort of terms do you try and negotiate for with China, America?

I'd make nice with the U.S. Withdraw from French Indochina, which was actually what really set the U.S. off and caused the oil embargo in the first place. The gains to the Japanese war effort by taking the French colonies were far less then the cost.

Japan was already engaged in what was likely an unwinnable war with China (too much China and too few Japanese of military age). To provoke the world's largest producer of materials and the source of 3/4 of your steel, 90%+ of your copper and the main oil exporter on the Planet was simply stupid. To engage a country that could outproduce you 15-1, had virtually all the resources it needed within its own borders and had double your population was beyond foolhardy.

It would have been incredibly difficult, perhaps even suicidal in the superheated climate of 1941 Japan, to have swallowed pride and accepted that the U.S. had Japan outmaneuvered and made the deal, but the deal had to be made.

lionhead · Dec 23, 2013

CalBear said:
I'd make nice with the U.S. Withdraw from French Indochina, which was actually what really set the U.S. off and caused the oil embargo in the first place. The gains to the Japanese war effort by taking the French colonies were far less then the cost.

i always thought the reason for the oil embargo was their war against China.

Would the US lift the oil embargo if they retreated from Indochina but continue to fight the ROC?

Blackfox5 · Dec 23, 2013

lionhead said:
Would the US lift the oil embargo if they retreated from Indochina but continue to fight the ROC?

This is one of those situations where once done, it is not as easy to undo. The US would not have initiated the embargo without the Japanese escalation of occupying Indochina. However, after the embargo was initiated, it becomes more difficult to end it. The US would likely require something more than simply going back to the status quo ante.

The US would likely tie an end to the embergo to Japan repudiating the Tripartite Pact and coming to a peace deal in China which Chiang Kai-Shek could accept. The first part is far easier than the second, since Chiang won't accept anything else than withdrawal of all Japanese troops, and the Japanese want to keep some thing from the debacle.

In other words, by the time the embargo was done, resolution of the "China Incident" was essential.

What information we have is that Japan was prepared to withdraw from much of China, but intended to keep Japanese troops in some areas (probably the five northern province of China) for a "suitable period", probably 25 years. That would be unacceptable to Chiang (and any other leader of China).

Historically, the US proposed that for withdrawing from southern Indochina and refraining from further escalation, the US would resume some trade relations for three months and then review the matter again. In other words, the US would only temporarily suspend the embargo, and a permanent end to the embargo would require additional concessions by Japan.

Hoist40 · Dec 23, 2013

CalBear said:
Specifically, the Philippines, especially the U.S. positions on Luzon, were ideally placed to interdict any movement of materials from the Malay Peninsula, DEI and Indochina, while also providing an ideal position to engage Japanese bases in Formosa that were critical to the conduct of the war in China. The U.S. base on Guam, while still undeveloped, was slated for improvements that would make Japan's position on Saipan (which was supposed to be temporary under League Mandate) completely untenable while Wake was nearly ideally placed to provide basing of long range air power to interdict the rest of the Mandates. Once you add in Johnson Island, Palmyra Atoll, and American Samoa, the U.S. had positions across the Pacific that would have rendered any Japanese effort to establish a defensive perimeter impossible.

.

But this is all a threat on paper, not reality. Just like keeping the US Fleet in Hawaii was a paper threat since the Navy did not have the ability to do more then a few raids on outlying Japanese islands due to a lack of support ships, troops and material.

In reality the Philippines could not defend itself let alone cut off Japan’s trade

Guam was undefended and it would take at least a year to build up anything

Wake was defended but was so small that it was vulnerable to bombing raids since any bomb that hit the island was probably going to hit something of value.
The rest of the US held islands were even weaker.

And if Japan takes the Dutch and British held islands it surrounds the Philippines, Guam, Wake making it very difficult for the US to supply these places. Even before the War the US had shifted its supply route to the Philippines south to avoid Japanese held islands but with the Japanese in control that route is cut off. Is the US going to continue to send vulnerable convoys to put more US troops into areas surrounded by the Japanese?

The Japanese were reacting to an unreal US capability to interfere with their plans. Yes the US was a danger but that danger was probably at least a year away. Better to take out two weak threats, Dutch and British and get the oil they needed and see what the US reaction would be. No matter what the Japanese have their six months of freedom since the US has little to stop them with.

CalBear · Dec 23, 2013

lionhead said:
i always thought the reason for the oil embargo was their war against China.

Would the US lift the oil embargo if they retreated from Indochina but continue to fight the ROC?

The U.S. huffed and puffed about China and the U.S. started to undercut the Japanese international trade position before the move into Indochina but it wasn't until 26 July of 1941, after the Japanese moved into French Indochina despite American and British warning not to, that the U.S. cut the flow of oil and scrap metal (which is actually vital to the production of new, high grade steel), along with ore and refined metals. The Oil embargo eliminate around 80% of Japanese imported oil, using 1939 figures (which, BTW, was over half of the DEI's total production in the same year, in 1939 the U.S. shipped 27.2 million barrels to Japan, the DEI produced 48.4 million barrels), while the strategic materials embargo cut of 90%+ of copper imports and most of their other metals.

The really serious problem though, was that the U.S. froze Japan's dollar accounts held in U.S. banks. At the time, post Fall of France, there were only two internationally accepted currencies, the Pound Sterling and U.S. dollars. The UK had made the decision to limit pound circulation to the Commonwealth and the U.S. so the American dollar was the only way to conduct international trade. Japan had very limited greenback reserves, and much of their Gold was held in U.S. or UK banks (with the lion's share in the U.S. Federal Reserve vaults in NYC). The yen was, internationally, pretty much worthless outside of areas under the control of the Japanese military (a situation similar to that that existed with the Soviet ruble during the Cold War), so the Japanese couldn't even go into the open market and buy from non-aligned countries in South America or elsewhere, they had no way to pay for goods.

Rubicon · Dec 23, 2013

There are several different questions that needs answering.

Strategically
Japan could in theory ignore the USA (and the Philippines) and just attack UK & Commonwealth, Dutch and French possession. Short term the Philippines isn't in -41 a threat to Japanese expansion or SLOC. Medium to long term is where the Philippines becomes a threat, the question then is how fast and with how much can the USA reinforce the Philippines? What political will is there to reinforce? MacArthur was offered an additional division (41st IIRC) prior to the war, but declined as he wished more equipment for the forces he already had at hand. So how much can be sent and at what pace? OTL is no real help to be honest as the political situation would be quite different and thus the pace of US rearmament (with the exception of the US navy). The pace of reinforcements to the Philippines will dictate the Japanese reactions towards the USA.

Politically
What would the situation be internally in the USA after a Japanese declaration of war against the UK, Netherlands etc. ? I sincerely doubt there would be enough support for a US declaration of war. And I'm not entirely certain Roosevelt would want one at that point either, but would press for a declaration of war on Germany maybe by the summer of -42.
But what would the internal political situation be in the USA after Japan declares war on the UK etc.? Without the isolationists discredited (but still losing strength) rearmament will suffer compared to OTL.

However when/if the USA declares war on Germany, Japan will be more or less forced into declaring war on the USA as the floodgates of war-materiel will be wide-opened for the Western Allies.

CalBear · Dec 23, 2013

Hoist40 said:
But this is all a threat on paper, not reality. Just like keeping the US Fleet in Hawaii was a paper threat since the Navy did not have the ability to do more then a few raids on outlying Japanese islands due to a lack of support ships, troops and material.

In reality the Philippines could not defend itself let alone cut off Japan’s trade

Guam was undefended and it would take at least a year to build up anything

Wake was defended but was so small that it was vulnerable to bombing raids since any bomb that hit the island was probably going to hit something of value.
The rest of the US held islands were even weaker.

And if Japan takes the Dutch and British held islands it surrounds the Philippines, Guam, Wake making it very difficult for the US to supply these places. Even before the War the US had shifted its supply route to the Philippines south to avoid Japanese held islands but with the Japanese in control that route is cut off. Is the US going to continue to send vulnerable convoys to put more US troops into areas surrounded by the Japanese?

The Japanese were reacting to an unreal US capability to interfere with their plans. Yes the US was a danger but that danger was probably at least a year away. Better to take out two weak threats, Dutch and British and get the oil they needed and see what the US reaction would be. No matter what the Japanese have their six months of freedom since the US has little to stop them with.

Paper threats are still threats, especially when you potential opponent can turn them from paper to real in a blink of an eye.

The so-called Pensacola Convoy (named after the lead escort vessel USS Pensacola CA-24) was in fact only days away from the PI when the war started. Iy would have delivered 52 A-24 dive bombers (with turned out to be in poor condition when finally uncrated in Australia), 18 P-40s, 20 75mm guns, 2,000 500 pound bombs, half a million rounds of .50 cal, and an additional National Guard brigade. This was just the tip of the iceberg, several more divisions of U.S. regular or fully trained and equipped NG formations were slated for movement to the islands, along with major shipments of fighter and bombers.

Wake was about two months from becoming a fully functional B-17 staging facility (complete with storage tanks for 250,000 gallon of fuel), Midway was being reinforced, the USN had established a Patrol Wing on Johnson Island, base and defensive improvements in American Samoa, Guam, and other points across the Pacific and Alaska had all been approved by Congress. What the Japanese realized was that, inside of two years, the U.S. Navy would be so powerful as to be invincible (as I frequently mention here, the capital ships and carriers that utterly destroyed Japan were all approved in the 1940 Navy Act).

Once the U.S. decided that it wanted to defend Luzon, Wake, Guam and any other position it had the money, manpower and construction/production capacity to do it. The Japanese understood this very well. The impact of the 1940 Two Ocean Navy Act, with its 18 fleet carrier, two more Iowa class BB, FIVE Montana class BB, Six Alaska class (yes, SIX of the %^$#% things) 27 cruisers, 115 destroyers, 15,000 aircraft and $50 million for "patrol and escort vessels", all approved in ONE Bill, that passed with virtually no opposition (vote in the House was 316-0, after less than an hour of debate) on the Japanese can not be overstated. The Navy had requested $4 billion, Congress voted $8 billion (the Fall of France had somewhat focused the Hill on military matters). As a comparison Japanese TOTAL military budget, which by 1938 was consuming 70%+ of the entire Japanese Government Budget, for 1938-40 inclusive, was ~19.7 billion yen, or less than $4.8 billion 1940 dollars.

The Two Ocean Navy Act, by itself, represented more than THREE YEARS of Japan's total Budget, and it was only the 1940 allocation. That doesn't even consider the huge increase for USAAF aircraft and the belated massive increase in spending for ground forces.

Japan had to 1. respect that sort of capability & 2. act before it was utterly outclassed. This is exactly what they did, attacking within days of when Zuikaku, finished her builder's trials, giving the Kido Butai the six fleet carriers that the Japanese planners had decided was the minimum needed to make the Pearl Harbor Raid.

Tokyo's window was incredibly narrow and they struck before it closed.

Astrodragon · Dec 23, 2013

There's one other factor to add to CalBears excellent analysis.

The British and the Dutch could, without a huge effort, be persuaded to at least not oppose and trade with Japan, because both countries were focussed on Europe.

The USA couldn't, and it was the USA that had instigated all the measures against Japan. To assume that the country responsible would have not stabbed you in the back would have been irresponsible for the Japanese.

There is also the issue of secret agreements between the USA and Britain if Japan attacked Malaya. In fact, nothing really came of the discussions until very shortly before PH, and even then any arrangements were limited and not firm commitments. But the Japanese didn't see it like that. They saw two western countries, cooperating significantly already against Germany, and couldn't believe there wasn't some sort of secret treaty. The Japanese were somewhat paranoid.

In addition, it wasn't only the USA reinforcing the Pacific. The British were half way through their own build-up, and when complete the Japanese wouldn't have got through Malaya. It was close as it was, and there are limits to what logistics you can push through Thailand. The Japanese really did choose the best time to hit their enemies, delay would have been fatal.

Carl Schwamberger · Dec 23, 2013

Hoist40 said:
But this is all a threat on paper, not reality. Just like keeping the US Fleet in Hawaii was a paper threat since the Navy did not have the ability to do more then a few raids on outlying Japanese islands due to a lack of support ships, troops and material.

That is all true for 6th Dec 1941. Eighteen month down the line the US would have what it needed for a unstoppable offensive & the Japanese knew it.

The US officially started its military mobilization in the summer/autum of 1940 with the passage of the War Powers acts & related emergency measures. By the spring of 1941 all Army & Navy reservists were on active duty, the national guard had been taken into Federal service, the military budget raised ten fold & then twentyfold. Aside from a half dozen new battleships under construction a similar number of new Essex class carriers were in construction or budgeted. Aircraft construction had gone from barely 2000 a year to over 10,000 and huge new factories were under construction.

The Japanese leaders were quite aware of all this & more and understood that if the US was not defeated now Japan would be two years later.

Curiousone · Dec 23, 2013

CalBear said:
Paper threats are still threats, especially when you potential opponent can turn them from paper to real in a blink of an eye.

The so-called Pensacola Convoy (named after the lead escort vessel USS Pensacola CA-24) was in fact only days away from the PI when the war started. Iy would have delivered 52 A-24 dive bombers (with turned out to be in poor condition when finally uncrated in Australia), 18 P-40s, 20 75mm guns, 2,000 500 pound bombs, half a million rounds of .50 cal, and an additional National Guard brigade. This was just the tip of the iceberg, several more divisions of U.S. regular or fully trained and equipped NG formations were slated for movement to the islands, along with major shipments of fighter and bombers.

Wake was about two months from becoming a fully functional B-17 staging facility (complete with storage tanks for 250,000 gallon of fuel), Midway was being reinforced, the USN had established a Patrol Wing on Johnson Island, base and defensive improvements in American Samoa, Guam, and other points across the Pacific and Alaska had all been approved by Congress. What the Japanese realized was that, inside of two years, the U.S. Navy would be so powerful as to be invincible (as I frequently mention here, the capital ships and carriers that utterly destroyed Japan were all approved in the 1940 Navy Act).

Once the U.S. decided that it wanted to defend Luzon, Wake, Guam and any other position it had the money, manpower and construction/production capacity to do it. The Japanese understood this very well. The impact of the 1940 Two Ocean Navy Act, with its 18 fleet carrier, two more Iowa class BB, FIVE Montana class BB, Six Alaska class (yes, SIX of the %^$#% things) 27 cruisers, 115 destroyers, 15,000 aircraft and $50 million for "patrol and escort vessels", all approved in ONE Bill, that passed with virtually no opposition (vote in the House was 316-0, after less than an hour of debate) on the Japanese can not be overstated. The Navy had requested $4 billion, Congress voted $8 billion (the Fall of France had somewhat focused the Hill on military matters). As a comparison Japanese TOTAL military budget, which by 1938 was consuming 70%+ of the entire Japanese Government Budget, for 1938-40 inclusive, was ~19.7 billion yen, or less than $4.8 billion 1940 dollars.

The Two Ocean Navy Act, by itself, represented more than THREE YEARS of Japan's total Budget, and it was only the 1940 allocation. That doesn't even consider the huge increase for USAAF aircraft and the belated massive increase in spending for ground forces.

Japan had to 1. respect that sort of capability & 2. act before it was utterly outclassed. This is exactly what they did, attacking within days of when Zuikaku, finished her builder's trials, giving the Kido Butai the six fleet carriers that the Japanese planners had decided was the minimum needed to make the Pearl Harbor Raid.

Tokyo's window was incredibly narrow and they struck before it closed.

Note those A-24 Dive bombers would likely have been operable given any delay in Japanese attacks that led to them being shipped to the Philippines.

I live in the city the convoy ended up in, have ancestors who were evacuating from the terror bombings in the North coming into port at the same time. Everything was in a rush, the civilian dockside labourers didn't have any info about unpacking the planes, solenoids stuck to the sides of the crates & so threw out the crates once they were emptied.